Insulation integrity of particle-contaminated GIS with dielectric coated electrodes

Electrical insulation performance of compressed gas insulated switchgear (GIS) and gas insulated transmission line (GITL) systems is adversely affected by metallic particle contaminants. Dielectric coatings help to improve the insulation performance in several ways. In this paper, dynamics of wire particle in a coaxial gas insulated transmission line (GITL) system with coated electrodes under AC voltage is studied using a computational algorithm. The possibility of the SF/sub 6/ gas insulation breakdown due to the presence of metallic contaminants was computed at different applied voltages and gas pressures. Results of laboratory experiments are presented.